Page 9 - 新思维科学学生用书7 样章

1 Cells

How have you tried to remember the difference between a cell wall and a cell
membrane? How successful do you think you have been?

Think like a scientist

Making a model of a plant cell
In this task, you will make a model to represent a plant cell. You will then think about

the strengths and limitations (weaknesses) of your model.

Here is a list of materials and objects you could use to make your model.
• transparent boxes
• cardboard boxes
• small and large plastic bags filled with water

• green peas, green beads or green grapes
• transparent food wrap
• empty plastic bags
• purple grapes

• coloured modelling material
In a group of three or four, discuss how you can use some of these materials and
objects to make a model of a plant cell. Then make your model.

Be ready to explain your model to others.

Questions
1 Compare your model cell with the models made by other groups.
Are there any features of your model that are better than those in the other
groups’ models?

Are there any features of other groups’ models that are better than yours?
2 Discuss how well your model cell represents a real plant cell.

eyepiece
Microscopes fine focussing knob
coarse focussing knob

Scientists who study living organisms high-power objective lens
often use microscopes to help them medium-power objective lens
to see very small things. low-power objective lens
microscope stage
The diagram shows a microscope.
Look at a real microscope and find mirror
all of these parts on it.

A microscope
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